The present invention relates to a serial ink jet printing head for liquid, electrically conductive ink, comprising an electrically insulating container for the ink, having a nozzle for the selective discharge of particles on ink, an electrode in contact with the ink and a counter-electrode adjacent to the nozzle, the discharge being caused by an electrical voltage pulse between the counter-electrode and the electrode.
In known printers of the above-indicated type, the container is connected by means of conduits to a larger-capacity tank which is disposed at a certain distance from the printing location. In the case of printers in which the head is mounted on a movable carriage, the tank is disposed on the fixed part of the machine and is connected to the container by way of flexible conduits of substantial length. A pump is required to pass the ink from the tank to the head, so that the printer is expensive to produce and complicated in operation.